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Date: Thu, 25 Sep 2008 13:48:31 -0400 (EDT)
From: Steven Rostedt <rostedt@goodmis.org>
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To: Mathieu Desnoyers <compudj@krystal.dyndns.org>
cc: Linus Torvalds <torvalds@linux-foundation.org>,
       linux-kernel@vger.kernel.org, Ingo Molnar <mingo@elte.hu>,
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       hch@lst.de, Martin Bligh <mbligh@google.com>,
       Christoph Hellwig <hch@infradead.org>,
       Steven Rostedt <srostedt@redhat.com>
Subject: Re: [RFC PATCH 1/2 v2] Unified trace buffer
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On Thu, 25 Sep 2008, Mathieu Desnoyers wrote:
> 
> Is there a reason to use delta between events rather than simply write
> the 27 LSBs that I would have missed ?

One answer is that your counter wrap problem is extended.

That is, you have 27 bits of time between each event to not worry about
wraps. But if you go against the page itself, the last event on that page
is more likely to suffer.

-- Steve